Diff Oil recommended but...

[ReVeNanTSS]

Originally Posted by Greenhornet2

I am not a fan of changing gear oil the a thicker viscosity. It may cause poor lubrication of the clutches and chatter/groan. Will it hurt? not really. For every day driving I would stick with 75/90. If you are getting a whine you have wear. Likely the side carrier bearing has some play so when the diff is loaded it is pushing the carrier to the side changing the tooth contact pattern making the whine. Road course or towing is the only time I'd use 75/140 personally.

Yes I have whine now. I dont know is it good to replace ring and pinion to 3.91. but too much alingment on there

[FasNuf]

Maybe I'm off base here but, road course change interval is something like every 6 hours! Yikes

[ReVeNanTSS]

Originally Posted by FasNuf

Maybe I'm off base here but, road course change interval is something like every 6 hours! Yikes

I don't get it

[Ashen L99]

Originally Posted by Avenging Orange

Start by changing the fluid. Make sure is has the friction modifier in it.
These cars are noisy by nature.
You should hear the diff with aftermarket bushings.

Yep, did the Delrin bushings from bmr and every once in a while I get a little gear noise. Shifting into gear I get a resounding tink, but that’s par for the course.

[RoadRunner70]

Sorry for resurrecting an old topic.

I also have a howling sound when accelerating. I replaced the main gear pinions by OEM AcDelco and all bearings. The howling became quieter, but did not go away.

Before that, about 2 months before the sound appeared, I changed the differential bushings to non-original Energy Suspension 3.1153R.

Today I saw in the Whiteline's catalog that their bushings affect the angle of the gears.

Whiteline's differential bushing solutions ensure pinion angles are maintained while delivering an improved gear shift resulting in reduced initial torque loss and greater power transfer to the wheels.

Could these aftermarket brand bushings affect to the diff noise ?